What We Did
Originally built by Ajax in the 1980s, the Vehicle Dynamic Area was in dire need of a new design and upgrade. Ajax was involved with every aspect of removal and reconstruction of the existing VDA and construction of a new 30-degree banked, high-speed parabolic return road. The newly designed 139,000 square-yard VDA pad required a 12-inch crushed limestone base course, 5 inches of HMA pavement, and a wearing surface of 1.5-inch HMA Superpave mixture specifically designed for a surface coefficient of friction of 90mu.
Stringent ride quality specs required an International Roughness Index (IDI) of 30 measured longitudinally and diagonally. An MDOT mix design was used for the project with three lifts required to make the 5-inch pavement. Keeping with Bosch’s “green” commitment, a portion of the existing asphalt pavement was recycled and mixed with on-site materials for the track’s shoulders.